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c _____________________________
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c
	subroutine comquat2(qq1,qq2,qresult)
	real qq1(4),qq2(4),qresult(4)
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c       PI=3.14159265
c
c  algorithm for forming resultant quaternion as Q1 x Q2^-1
c  where Q2 follows Q1, i.e. is the second rotation;
c  note change of signs to get inverse of second orientation
c
	qresult(1)=qq1(1)*qq2(4)-qq1(4)*qq2(1)
     &	+qq1(2)*qq2(3)-qq1(3)*qq2(2)
	qresult(2)=qq1(2)*qq2(4)-qq1(4)*qq2(2)
     &	+qq1(3)*qq2(1)-qq1(1)*qq2(3)
	qresult(3)=qq1(3)*qq2(4)-qq1(4)*qq2(3)
     &	+qq1(1)*qq2(2)-qq1(2)*qq2(1)
	qresult(4)=qq1(4)*qq2(4)+qq1(1)*qq2(1)
     &	+qq1(2)*qq2(2)+qq1(3)*qq2(3)
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c	write(*,*) 'qresult ',qresult
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	return
	end
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c
c _____________________________
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c